The colors in the bird’s feather are pigmentary or structural. Structural colors are produced by the light scattering from nano-arrangements of the molecules that form the feather, and are classified as iridescent and non-iridescent colors structural (NISC). Nanostructures that produces NISC is the matrix made of β-keratin and air, below which is a layer of melanosomes that absorbs non-coherently scattered light from the layer above. The melanosomes preserve on the surface of the fossil, and their shape vary with the color they produce. The shape of the melanosomes in the NISC, and their detection in the fossil record has not yet been researched. The melanosomes from recent feathers are isolated and their shape is determined. Statistical analysis of their length and width showed that they overlap with grey color melanosomes. Sample of unknown melanosomes from the surface of the fossil Eocoracias brachyptera from Messel pit in Germany was compared with the other melanosomes categories. Reconstruction of the fossils combined with ancestral state reconstruction showed that bird was blue. With transmission electron microscopy, the importance of the size of NISC melanosomes was explained from the aspect of the development of the feather.